Section 06 PRODUCTS OF THE CHEMICAL OR ALLIED INDUSTRIES 28 INORGANIC CHEMICALS; ORGANIC OR INORGANIC COMPOUNDS OF PRECIOUS METAL, OFRARE-EARTH METALS, OF RADIOACTIVE ELEMENTS OR OF ISOTOPES 28 04 HYDROGEN, RARE GASES AND OTHER NON-METALS. 28 04 21 ARGON Commodity Code Description 28 04 21 00 ARGON